I concede (sort of)
I looked far and wide to find support for my position and found little. All the "experts on terrorism" parrot your side. The only authorities on my side were Rumsfeld and General Meyers and since the current administration is entirely made up of "liars†I’ll forfeit their remarks.
Note that your position was "imagined" before the war started. Without solid empirical evidence, the experts are declaring their hypothesis "proven". The fact is, estimates range from a few thousand fighters to 40,000 hard core insurgents which tells me no one really knows but it's safe to assume that their numbers are swelling.
As far as "Exporting Terrorism" goes, yeah, a couple of yah-hoos drove across the boarder from Iraq into Jordan....